The labyrinth fish, whose range is limited to Asia and Africa, have as their common characteristic an additional respiratory organ. These are situated at the side of each gill cavity and are designed to act as back-up organs to supplement the inadequate gills in poorly oxygenated water. The fish rise to the surface to obtain additional oxygen from the air. If they are prevented from doing this, they may suffocate. As these fish are sensitive to cold air, their aquarium should be covered.

In some species, the ventral fins have evolved into threads or filaments that act as sensitive, organs containing sensory cells. Most species of the labyrinth fish build a nest of bubbles at the surface, usually attached to floating plants. The young fry are looked after in these bubble-nests by the male, which takes care of the brood until the young fry are free swimming and take food independently.

Almost all labyrinth fish species need plants in the aquarium where they can take refuge from bright light and whenever they are frightened, so a dark tank bottom is a plus. Most species are not very demanding when it comes to the type of water and food they require, they are well suited to the community tank, and highly recommended for beginners. They are best kept together, the exception to this being the Betta species. There should only be one male.